The production of amino acids, especially by biosynthesis, e.g. fermentation, has become increasingly important in recent years. These amino acids have been found to be useful intermediates in the production of food flavorings and food supplements and also in medical research. U.S. Pat. No. 3,616,224, for example, teaches the synthesis of amino acids from a micro-organism of the species Schromobacter methanolphilia or Pseudomonas insueta while U.S. Pat. Nos. 3,660,235 and 3,759,790 culture Brevibacterium, Corynebacterium, Anthrobacter, Bacillus, Candida and others. U.S. Pat. Nos. 3,909,353; 4,016,037 and 4,403,003 also teach methods of amino acid production.
One of the basic problems one faces in the production of amino acids, especially in aqueous media, is the ultimate recovery of the amino acid once its production is complete.
In all of the above-cited U.S. patents, the amino acid product is recovered by means of ion exchange resins, filtration, centrifugation, precipitation at the isoelectric point, activated carbon treatment and the like.
Recently, German Offen. No. 2822870, was published describing the extraction of amino acids from aqueous solutions with a non-aromatic C.sub.4 -C.sub.8 ketone containing cumenesulfonic acid partially neutralized by alkali.
While these techniques for the isolation of amino acids from aqueous solution have proven reasonably successful, the need still exists for means for amino acid recovery wherein increased yields are achieved and/or less expensive extractants are employed.